 /*******************************************************************************
  * Copyright (c) 2000, 2007 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.forms.widgets;

 import java.io.InputStream ;
 import java.util.ArrayList ;
 import java.util.Enumeration ;
 import java.util.Hashtable ;

 import org.eclipse.core.runtime.ListenerList;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.SWTException;
 import org.eclipse.swt.accessibility.ACC;
 import org.eclipse.swt.accessibility.Accessible;
 import org.eclipse.swt.accessibility.AccessibleAdapter;
 import org.eclipse.swt.accessibility.AccessibleControlAdapter;
 import org.eclipse.swt.accessibility.AccessibleControlEvent;
 import org.eclipse.swt.accessibility.AccessibleEvent;
 import org.eclipse.swt.custom.ScrolledComposite;
 import org.eclipse.swt.dnd.Clipboard;
 import org.eclipse.swt.dnd.TextTransfer;
 import org.eclipse.swt.dnd.Transfer;
 import org.eclipse.swt.events.DisposeEvent;
 import org.eclipse.swt.events.DisposeListener;
 import org.eclipse.swt.events.FocusEvent;
 import org.eclipse.swt.events.FocusListener;
 import org.eclipse.swt.events.MenuEvent;
 import org.eclipse.swt.events.MenuListener;
 import org.eclipse.swt.events.MouseEvent;
 import org.eclipse.swt.events.MouseListener;
 import org.eclipse.swt.events.MouseMoveListener;
 import org.eclipse.swt.events.MouseTrackListener;
 import org.eclipse.swt.events.PaintEvent;
 import org.eclipse.swt.events.PaintListener;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.events.SelectionListener;
 import org.eclipse.swt.graphics.Color;
 import org.eclipse.swt.graphics.Font;
 import org.eclipse.swt.graphics.FontMetrics;
 import org.eclipse.swt.graphics.GC;
 import org.eclipse.swt.graphics.Image;
 import org.eclipse.swt.graphics.Point;
 import org.eclipse.swt.graphics.Rectangle;
 import org.eclipse.swt.widgets.Canvas;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.swt.widgets.Event;
 import org.eclipse.swt.widgets.Layout;
 import org.eclipse.swt.widgets.Listener;
 import org.eclipse.swt.widgets.Menu;
 import org.eclipse.swt.widgets.MenuItem;
 import org.eclipse.swt.widgets.TypedListener;
 import org.eclipse.ui.forms.HyperlinkSettings;
 import org.eclipse.ui.forms.events.HyperlinkEvent;
 import org.eclipse.ui.forms.events.IHyperlinkListener;
 import org.eclipse.ui.internal.forms.Messages;
 import org.eclipse.ui.internal.forms.widgets.ControlSegment;
 import org.eclipse.ui.internal.forms.widgets.FormTextModel;
 import org.eclipse.ui.internal.forms.widgets.FormUtil;
 import org.eclipse.ui.internal.forms.widgets.IFocusSelectable;
 import org.eclipse.ui.internal.forms.widgets.IHyperlinkSegment;
 import org.eclipse.ui.internal.forms.widgets.ImageSegment;
 import org.eclipse.ui.internal.forms.widgets.Locator;
 import org.eclipse.ui.internal.forms.widgets.Paragraph;
 import org.eclipse.ui.internal.forms.widgets.ParagraphSegment;
 import org.eclipse.ui.internal.forms.widgets.SelectionData;
 import org.eclipse.ui.internal.forms.widgets.TextSegment;

 /**
  * This class is a read-only text control that is capable of rendering wrapped
  * text. Text can be rendered as-is or by parsing the formatting XML tags.
  * Independently, words that start with http:// can be converted into hyperlinks
  * on the fly.
  * <p>
  * When configured to use formatting XML, the control requires the root element
  * <code>form</code> to be used. The following tags can be children of the
  * <code>form</code> element:
  * </p>
  * <ul>
  * <li><b>p </b>- for defining paragraphs. The following attributes are
  * allowed:
  * <ul>
  * <li><b>vspace </b>- if set to 'false', no vertical space will be added
  * (default is 'true')</li>
  * </ul>
  * </li>
  * <li><b>li </b>- for defining list items. The following attributes are
  * allowed:
  * <ul>
  * <li><b>vspace </b>- the same as with the <b>p </b> tag</li>
  * <li><b>style </b>- could be 'bullet' (default), 'text' and 'image'</li>
  * <li><b>value </b>- not used for 'bullet'. For text, it is the value of the
  * text that is rendered as a bullet. For image, it is the href of the image to
  * be rendered as a bullet.</li>
  * <li><b>indent </b>- the number of pixels to indent the text in the list item
  * </li>
  * <li><b>bindent </b>- the number of pixels to indent the bullet itself</li>
  * </ul>
  * </li>
  * </ul>
  * <p>
  * Text in paragraphs and list items will be wrapped according to the width of
  * the control. The following tags can appear as children of either <b>p </b> or
  * <b>li </b> elements:
  * <ul>
  * <li><b>img </b>- to render an image. Element accepts attribute 'href' that
  * is a key to the <code>Image</code> set using 'setImage' method. Vertical
  * position of image relative to surrounding text is optionally controlled by
  * the attribute <b>align</b> that can have values <b>top</b>, <b>middle</b>
  * and <b>bottom</b></li>
  * <li><b>a </b>- to render a hyperlink. Element accepts attribute 'href' that
  * will be provided to the hyperlink listeners via HyperlinkEvent object. The
  * element also accepts 'nowrap' attribute (default is false). When set to
  * 'true', the hyperlink will not be wrapped. Hyperlinks automatically created
  * when 'http://' is encountered in text are not wrapped.</li>
  * <li><b>b </b>- the enclosed text will use bold font.</li>
  * <li><b>br </b>- forced line break (no attributes).</li>
  * <li><b>span </b>- the enclosed text will have the color and font specified
  * in the element attributes. Color is provided using 'color' attribute and is a
  * key to the Color object set by 'setColor' method. Font is provided using
  * 'font' attribute and is a key to the Font object set by 'setFont' method. As with
  * hyperlinks, it is possible to block wrapping by setting 'nowrap' to true
  * (false by default).
  * </li>
  * <li><b>control (new in 3.1)</b> - to place a control that is a child of the
  * text control. Element accepts attribute 'href' that is a key to the Control
  * object set using 'setControl' method. Optionally, attribute 'fill' can be set
  * to <code>true</code> to make the control fill the entire width of the text.
  * Form text is not responsible for creating or disposing controls, it only
  * places them relative to the surrounding text. Similar to <b>img</b>,
  * vertical position of the control can be set using the <b>align</b>
  * attribute. In addition, <b>width</b> and <b>height</b> attributes can
  * be used to force the dimensions of the control. If not used,
  * the preferred control size will be used.
  * </ul>
  * <p>
  * None of the elements can nest. For example, you cannot have <b>b </b> inside
  * a <b>span </b>. This was done to keep everything simple and transparent.
  * Since 3.1, an exception to this rule has been added to support nesting images
  * and text inside the hyperlink tag (<b>a</b>). Image enclosed in the
  * hyperlink tag acts as a hyperlink, can be clicked on and can accept and
  * render selection focus. When both text and image is enclosed, selection and
  * rendering will affect both as a single hyperlink.
  * </p>
  * <p>
  * Since 3.1, it is possible to select text. Text selection can be
  * programmatically accessed and also copied to clipboard. Non-textual objects
  * (images, controls etc.) in the selection range are ignored.
  * <p>
  * Care should be taken when using this control. Form text is not an HTML
  * browser and should not be treated as such. If you need complex formatting
  * capabilities, use Browser widget. If you need editing capabilities and
  * font/color styles of text segments is all you need, use StyleText widget.
  * Finally, if all you need is to wrap text, use SWT Label widget and create it
  * with SWT.WRAP style.
  *
  * @see FormToolkit
  * @see TableWrapLayout
  * @since 3.0
  */
 public class FormText extends Canvas {
     /**
      * The object ID to be used when registering action to handle URL hyperlinks
      * (those that should result in opening the web browser). Value is
      * "urlHandler".
      */
     public static final String URL_HANDLER_ID = "urlHandler"; //$NON-NLS-1$

     /**
      * Value of the horizontal margin (default is 0).
      */
     public int marginWidth = 0;

     /**
      * Value of tue vertical margin (default is 1).
      */
     public int marginHeight = 1;

     // private fields
 //TODO We should remove the dependency on Platform
 private static final boolean DEBUG_TEXT = false;//"true".equalsIgnoreCase(Platform.getDebugOption(FormUtil.DEBUG_TEXT));
 private static final boolean DEBUG_TEXTSIZE = false;//"true".equalsIgnoreCase(Platform.getDebugOption(FormUtil.DEBUG_TEXTSIZE));

     private static final boolean DEBUG_FOCUS = false;//"true".equalsIgnoreCase(Platform.getDebugOption(FormUtil.DEBUG_FOCUS));

     private boolean hasFocus;

     private boolean paragraphsSeparated = true;

     private FormTextModel model;

     private ListenerList listeners;

     private Hashtable resourceTable = new Hashtable ();

     private IHyperlinkSegment entered;

     private IHyperlinkSegment armed;

     private boolean mouseFocus = false;

     private boolean controlFocusTransfer = false;

     private boolean inSelection = false;

     private SelectionData selData;

     private static final String INTERNAL_MENU = "__internal_menu__"; //$NON-NLS-1$

     private static final String CONTROL_KEY = "__segment__"; //$NON-NLS-1$

     private class FormTextLayout extends Layout implements ILayoutExtension {
         public FormTextLayout() {
         }

         public int computeMaximumWidth(Composite parent, boolean changed) {
             return computeSize(parent, SWT.DEFAULT, SWT.DEFAULT, changed).x;
         }

         public int computeMinimumWidth(Composite parent, boolean changed) {
             return computeSize(parent, 5, SWT.DEFAULT, true).x;
         }

         /*
          * @see Layout#computeSize(Composite, int, int, boolean)
          */
         public Point computeSize(Composite composite, int wHint, int hHint,
                 boolean changed) {
             long start = 0;

             if (DEBUG_TEXT)
                 start = System.currentTimeMillis();
             int innerWidth = wHint;
             if (innerWidth != SWT.DEFAULT)
                 innerWidth -= marginWidth * 2;
             Point textSize = computeTextSize(innerWidth);
             int textWidth = textSize.x + 2 * marginWidth;
             int textHeight = textSize.y + 2 * marginHeight;
             Point result = new Point(textWidth, textHeight);
             if (DEBUG_TEXT) {
                 long stop = System.currentTimeMillis();
                 System.out.println("FormText computeSize: " + (stop - start) //$NON-NLS-1$
 + "ms"); //$NON-NLS-1$
 }
             if (DEBUG_TEXTSIZE) {
                 System.out.println("FormText ("+model.getAccessibleText()+"), computeSize: wHint="+wHint+", result="+result); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
 }
             return result;
         }

         private Point computeTextSize(int wHint) {
             Paragraph[] paragraphs = model.getParagraphs();
             GC gc = new GC(FormText.this);
             gc.setFont(getFont());
             Locator loc = new Locator();
             int width = wHint != SWT.DEFAULT ? wHint : 0;
             FontMetrics fm = gc.getFontMetrics();
             int lineHeight = fm.getHeight();
             boolean selectableInTheLastRow = false;
             for (int i = 0; i < paragraphs.length; i++) {
                 Paragraph p = paragraphs[i];
                 if (i > 0 && getParagraphsSeparated()
                         && p.getAddVerticalSpace())
                     loc.y += getParagraphSpacing(lineHeight);
                 loc.rowHeight = 0;
                 loc.indent = p.getIndent();
                 loc.x = p.getIndent();
                 ParagraphSegment[] segments = p.getSegments();
                 if (segments.length > 0) {
                     selectableInTheLastRow = false;
                     int pwidth = 0;
                     for (int j = 0; j < segments.length; j++) {
                         ParagraphSegment segment = segments[j];
                         segment.advanceLocator(gc, wHint, loc, resourceTable,
                                 false);
                         if (wHint != SWT.DEFAULT) {
                             width = Math.max(width, loc.width);
                         } else {
                             pwidth += loc.width;
                         }
                         if (segment instanceof IFocusSelectable)
                             selectableInTheLastRow = true;
                     }
                     if (wHint == SWT.DEFAULT)
                         width = Math.max(width, pwidth);
                     loc.y += loc.rowHeight;
                 } else {
                     // empty new line
 loc.y += lineHeight;
                 }
             }
             gc.dispose();
             if (selectableInTheLastRow)
                 loc.y += 1;
             return new Point(width, loc.y);
         }

         protected void layout(Composite composite, boolean flushCache) {
             long start = 0;

             if (DEBUG_TEXT) {
                 start = System.currentTimeMillis();
             }
             selData = null;
             Rectangle carea = composite.getClientArea();
             if (DEBUG_TEXTSIZE) {
                 System.out.println("FormText layout ("+model.getAccessibleText()+"), carea="+carea); //$NON-NLS-1$ //$NON-NLS-2$
 }
             GC gc = new GC(composite);
             gc.setFont(getFont());
             ensureBoldFontPresent(getFont());
             gc.setForeground(getForeground());
             gc.setBackground(getBackground());

             Locator loc = new Locator();
             loc.marginWidth = marginWidth;
             loc.marginHeight = marginHeight;
             loc.x = marginWidth;
             loc.y = marginHeight;
             FontMetrics fm = gc.getFontMetrics();
             int lineHeight = fm.getHeight();

             Paragraph[] paragraphs = model.getParagraphs();
             IHyperlinkSegment selectedLink = getSelectedLink();
             for (int i = 0; i < paragraphs.length; i++) {
                 Paragraph p = paragraphs[i];
                 if (i > 0 && paragraphsSeparated && p.getAddVerticalSpace())
                     loc.y += getParagraphSpacing(lineHeight);
                 loc.indent = p.getIndent();
                 loc.resetCaret();
                 loc.rowHeight = 0;
                 p.layout(gc, carea.width, loc, lineHeight, resourceTable,
                         selectedLink);
             }
             gc.dispose();
             if (DEBUG_TEXT) {
                 long stop = System.currentTimeMillis();
                 System.out.println("FormText.layout: " + (stop - start) + "ms"); //$NON-NLS-1$ //$NON-NLS-2$
 }
         }
     }

     /**
      * Contructs a new form text widget in the provided parent and using the
      * styles.
      *
      * @param parent
      * form text parent control
      * @param style
      * the widget style
      */
     public FormText(Composite parent, int style) {
         super(parent, SWT.NO_BACKGROUND | SWT.WRAP | style);
         setLayout(new FormTextLayout());
         model = new FormTextModel();
         addDisposeListener(new DisposeListener() {
             public void widgetDisposed(DisposeEvent e) {
                 model.dispose();
                 disposeResourceTable(true);
             }
         });
         addPaintListener(new PaintListener() {
             public void paintControl(PaintEvent e) {
                 paint(e);
             }
         });
         addListener(SWT.KeyDown, new Listener() {
             public void handleEvent(Event e) {
                 if (e.character == '\r') {
                     activateSelectedLink();
                     return;
                 }
             }
         });
         addListener(SWT.Traverse, new Listener() {
             public void handleEvent(Event e) {
                 if (DEBUG_FOCUS)
                     System.out.println("Traversal: " + e); //$NON-NLS-1$
 switch (e.detail) {
                 case SWT.TRAVERSE_PAGE_NEXT:
                 case SWT.TRAVERSE_PAGE_PREVIOUS:
                 case SWT.TRAVERSE_ARROW_NEXT:
                 case SWT.TRAVERSE_ARROW_PREVIOUS:
                     e.doit = false;
                     return;
                 }
                 if (!model.hasFocusSegments()) {
                     e.doit = true;
                     return;
                 }
                 if (e.detail == SWT.TRAVERSE_TAB_NEXT)
                     e.doit = advance(true);
                 else if (e.detail == SWT.TRAVERSE_TAB_PREVIOUS)
                     e.doit = advance(false);
                 else if (e.detail != SWT.TRAVERSE_RETURN)
                     e.doit = true;
             }
         });
         addFocusListener(new FocusListener() {
             public void focusGained(FocusEvent e) {
                 if (!hasFocus) {
                     hasFocus = true;
                     if (DEBUG_FOCUS) {
                         System.out.println("FormText: focus gained"); //$NON-NLS-1$
 }
                     if (!mouseFocus && !controlFocusTransfer) {
                         handleFocusChange();
                     }
                 }
             }

             public void focusLost(FocusEvent e) {
                 if (DEBUG_FOCUS) {
                     System.out.println("FormText: focus lost"); //$NON-NLS-1$
 }
                 if (hasFocus) {
                     hasFocus = false;
                     if (!controlFocusTransfer)
                         handleFocusChange();
                 }
             }
         });
         addMouseListener(new MouseListener() {
             public void mouseDoubleClick(MouseEvent e) {
             }

             public void mouseDown(MouseEvent e) {
                 // select a link
 handleMouseClick(e, true);
             }

             public void mouseUp(MouseEvent e) {
                 // activate a link
 handleMouseClick(e, false);
             }
         });
         addMouseTrackListener(new MouseTrackListener() {
             public void mouseEnter(MouseEvent e) {
                 handleMouseMove(e);
             }

             public void mouseExit(MouseEvent e) {
                 if (entered != null) {
                     exitLink(entered, e.stateMask);
                     paintLinkHover(entered, false);
                     entered = null;
                     setCursor(null);
                 }
             }

             public void mouseHover(MouseEvent e) {
                 handleMouseHover(e);
             }
         });
         addMouseMoveListener(new MouseMoveListener() {
             public void mouseMove(MouseEvent e) {
                 handleMouseMove(e);
             }
         });
         initAccessible();
         ensureBoldFontPresent(getFont());
         createMenu();
         // we will handle traversal of controls, if any
 setTabList(new Control[] {});
     }

     /**
      * Test for focus.
      *
      * @return <samp>true </samp> if the widget has focus.
      */
     public boolean getFocus() {
         return hasFocus;
     }

     /**
      * Test if the widget is currently processing the text it is about to
      * render.
      *
      * @return <samp>true </samp> if the widget is still loading the text,
      * <samp>false </samp> otherwise.
      * @deprecated not used any more - returns <code>false</code>
      */
     public boolean isLoading() {
         return false;
     }

     /**
      * Returns the text that will be shown in the control while the real content
      * is loading.
      *
      * @return loading text message
      * @deprecated loading text is not used since 3.1
      */
     public String getLoadingText() {
         return null;
     }

     /**
      * Sets the text that will be shown in the control while the real content is
      * loading. This is significant when content to render is loaded from the
      * input stream that was created from a remote URL, and the time to load the
      * entire content is nontrivial.
      *
      * @param loadingText
      * loading text message
      * @deprecated use setText(loadingText, false, false);
      */
     public void setLoadingText(String loadingText) {
         setText(loadingText, false, false);
     }

     /**
      * If paragraphs are separated, spacing will be added between them.
      * Otherwise, new paragraphs will simply start on a new line with no
      * spacing.
      *
      * @param value
      * <samp>true </samp> if paragraphs are separated, </samp> false
      * </samp> otherwise.
      */
     public void setParagraphsSeparated(boolean value) {
         paragraphsSeparated = value;
     }

     /**
      * Tests if there is some inter-paragraph spacing.
      *
      * @return <samp>true </samp> if paragraphs are separated, <samp>false
      * </samp> otherwise.
      */
     public boolean getParagraphsSeparated() {
         return paragraphsSeparated;
     }

     /**
      * Registers the image referenced by the provided key.
      * <p>
      * For <samp>img </samp> tags, an object of a type <samp>Image </samp> must
      * be registered using the key equivalent to the value of the <samp>href
      * </samp> attribute used in the tag.
      *
      * @param key
      * unique key that matches the value of the <samp>href </samp>
      * attribute.
      * @param image
      * an object of a type <samp>Image </samp>.
      */
     public void setImage(String key, Image image) {
         resourceTable.put("i." + key, image); //$NON-NLS-1$
 }

     /**
      * Registers the color referenced by the provided key.
      * <p>
      * For <samp>span </samp> tags, an object of a type <samp>Color </samp> must
      * be registered using the key equivalent to the value of the <samp>color
      * </samp> attribute.
      *
      * @param key
      * unique key that matches the value of the <samp>color </samp>
      * attribute.
      * @param color
      * an object of the type <samp>Color </samp> or <samp>null</samp>
      * if the key needs to be cleared.
      */
     public void setColor(String key, Color color) {
         String fullKey = "c." + key; //$NON-NLS-1$
 if (color == null)
             resourceTable.remove(fullKey);
         else
             resourceTable.put(fullKey, color);
     }

     /**
      * Registers the font referenced by the provided key.
      * <p>
      * For <samp>span </samp> tags, an object of a type <samp>Font </samp> must
      * be registered using the key equivalent to the value of the <samp>font
      * </samp> attribute.
      *
      * @param key
      * unique key that matches the value of the <samp>font </samp>
      * attribute.
      * @param font
      * an object of the type <samp>Font </samp> or <samp>null</samp>
      * if the key needs to be cleared.
      */
     public void setFont(String key, Font font) {
         String fullKey = "f." + key; //$NON-NLS-1$
 if (font == null)
             resourceTable.remove(fullKey);
         else
             resourceTable.put(fullKey, font);
         model.clearCache(fullKey);
     }

     /**
      * Registers the control referenced by the provided key.
      * <p>
      * For <samp>control</samp> tags, an object of a type <samp>Control</samp>
      * must be registered using the key equivalent to the value of the
      * <samp>control</samp> attribute.
      *
      * @param key
      * unique key that matches the value of the <samp>control</samp>
      * attribute.
      * @param control
      * an object of the type <samp>Control</samp> or <samp>null</samp>
      * if the existing control at the specified key needs to be
      * removed.
      * @since 3.1
      */
     public void setControl(String key, Control control) {
         String fullKey = "o." + key; //$NON-NLS-1$
 if (control == null)
             resourceTable.remove(fullKey);
         else
             resourceTable.put(fullKey, control);
     }

     /**
      * Sets the font to use to render the default text (text that does not have
      * special font property assigned). Bold font will be constructed from this
      * font.
      *
      * @param font
      * the default font to use
      */
     public void setFont(Font font) {
         super.setFont(font);
         model.clearCache(null);
         Font boldFont = (Font) resourceTable.get(FormTextModel.BOLD_FONT_ID);
         if (boldFont != null) {
             boldFont.dispose();
             resourceTable.remove(FormTextModel.BOLD_FONT_ID);
         }
         ensureBoldFontPresent(getFont());
     }

     /**
      * Sets the provided text. Text can be rendered as-is, or by parsing the
      * formatting tags. Optionally, sections of text starting with http:// will
      * be converted to hyperlinks.
      *
      * @param text
      * the text to render
      * @param parseTags
      * if <samp>true </samp>, formatting tags will be parsed.
      * Otherwise, text will be rendered as-is.
      * @param expandURLs
      * if <samp>true </samp>, URLs found in the untagged text will be
      * converted into hyperlinks.
      */
     public void setText(String text, boolean parseTags, boolean expandURLs) {
         disposeResourceTable(false);
         entered = null;
         if (parseTags)
             model.parseTaggedText(text, expandURLs);
         else
             model.parseRegularText(text, expandURLs);
         hookControlSegmentFocus();
         layout();
         redraw();
     }

     /**
      * Sets the contents of the stream. Optionally, URLs in untagged text can be
      * converted into hyperlinks. The caller is responsible for closing the
      * stream.
      *
      * @param is
      * stream to render
      * @param expandURLs
      * if <samp>true </samp>, URLs found in untagged text will be
      * converted into hyperlinks.
      */
     public void setContents(InputStream is, boolean expandURLs) {
         entered = null;
         disposeResourceTable(false);
         model.parseInputStream(is, expandURLs);
         hookControlSegmentFocus();
         layout();
         redraw();
     }

     private void hookControlSegmentFocus() {
         Paragraph[] paragraphs = model.getParagraphs();
         if (paragraphs == null)
             return;
         Listener listener = new Listener() {
             public void handleEvent(Event e) {
                 switch (e.type) {
                 case SWT.FocusIn:
                     if (!controlFocusTransfer)
                         syncControlSegmentFocus((Control) e.widget);
                     break;
                 case SWT.Traverse:
                     if (DEBUG_FOCUS)
                         System.out.println("Control traversal: " + e); //$NON-NLS-1$
 switch (e.detail) {
                     case SWT.TRAVERSE_PAGE_NEXT:
                     case SWT.TRAVERSE_PAGE_PREVIOUS:
                     case SWT.TRAVERSE_ARROW_NEXT:
                     case SWT.TRAVERSE_ARROW_PREVIOUS:
                         e.doit = false;
                         return;
                     }
                     Control c = (Control) e.widget;
                     ControlSegment segment = (ControlSegment) c
                             .getData(CONTROL_KEY);
                     if (e.detail == SWT.TRAVERSE_TAB_NEXT)
                         e.doit = advanceControl(c, segment, true);
                     else if (e.detail == SWT.TRAVERSE_TAB_PREVIOUS)
                         e.doit = advanceControl(c, segment, false);
                     if (!e.doit)
                         e.detail = SWT.TRAVERSE_NONE;
                     break;
                 }
             }
         };
         for (int i = 0; i < paragraphs.length; i++) {
             Paragraph p = paragraphs[i];
             ParagraphSegment[] segments = p.getSegments();
             for (int j = 0; j < segments.length; j++) {
                 if (segments[j] instanceof ControlSegment) {
                     ControlSegment cs = (ControlSegment) segments[j];
                     Control c = cs.getControl(resourceTable);
                     if (c != null) {
                         if (c.getData(CONTROL_KEY) == null) {
                             // first time - hook
 c.setData(CONTROL_KEY, cs);
                             attachTraverseListener(c, listener);
                         }
                     }
                 }
             }
         }
     }

     private void attachTraverseListener(Control c, Listener listener) {
         if (c instanceof Composite) {
             Composite parent = (Composite) c;
             Control[] children = parent.getChildren();
             for (int i = 0; i < children.length; i++) {
                 attachTraverseListener(children[i], listener);
             }
             if (c instanceof Canvas) {
                 // If Canvas, the control iteself can accept
 // traverse events and should be monitored
 c.addListener(SWT.Traverse, listener);
                 c.addListener(SWT.FocusIn, listener);
             }
         } else {
             c.addListener(SWT.Traverse, listener);
             c.addListener(SWT.FocusIn, listener);
         }
     }

     /**
      * If we click on the control randomly, our internal book-keeping will be
      * off. We need to update the model and mark the control segment and
      * currently selected. Hyperlink that may have had focus must also be
      * exited.
      *
      * @param control
      * the control that got focus
      */
     private void syncControlSegmentFocus(Control control) {
         ControlSegment cs = null;

         while (control != null) {
             cs = (ControlSegment) control.getData(CONTROL_KEY);
             if (cs != null)
                 break;
             control = control.getParent();
         }
         if (cs == null)
             return;
         IFocusSelectable current = model.getSelectedSegment();
         // If the model and the control match, all is well
 if (current == cs)
             return;
         IHyperlinkSegment oldLink = null;
         if (current != null && current instanceof IHyperlinkSegment) {
             oldLink = (IHyperlinkSegment) current;
             exitLink(oldLink, SWT.NULL);
         }
         if (DEBUG_FOCUS)
             System.out.println("Sync control: " + cs + ", oldLink=" + oldLink); //$NON-NLS-1$ //$NON-NLS-2$
 model.select(cs);
         if (oldLink != null)
             paintFocusTransfer(oldLink, null);
         // getAccessible().setFocus(model.getSelectedSegmentIndex());
 }

     private boolean advanceControl(Control c, ControlSegment segment,
             boolean next) {
         Composite parent = c.getParent();
         if (parent == this) {
             // segment-level control
 IFocusSelectable nextSegment = model.getNextFocusSegment(next);
             if (nextSegment != null) {
                 controlFocusTransfer = true;
                 super.forceFocus();
                 controlFocusTransfer = false;
                 model.select(segment);
                 return advance(next);
             }
             // nowhere to go
 return setFocusToNextSibling(this, next);
         }
         if (setFocusToNextSibling(c, next))
             return true;
         // still here - must go one level up
 segment = (ControlSegment) parent.getData(CONTROL_KEY);
         return advanceControl(parent, segment, next);
     }

     private boolean setFocusToNextSibling(Control c, boolean next) {
         Composite parent = c.getParent();
         Control[] children = parent.getTabList();
         for (int i = 0; i < children.length; i++) {
             Control child = children[i];
             if (child == c) {
                 // here
 if (next) {
                     for (int j = i + 1; j < children.length; j++) {
                         Control nc = children[j];
                         if (nc.setFocus())
                             return false;
                     }
                 } else {
                     for (int j = i - 1; j >= 0; j--) {
                         Control pc = children[j];
                         if (pc.setFocus())
                             return false;
                     }
                 }
             }
         }
         return false;
     }

     /**
      * Controls whether whitespace inside paragraph and list items is
      * normalized. Note that the new value will not affect the current text in
      * the control, only subsequent calls to <code>setText</code> or
      * <code>setContents</code>.
      * <p>
      * If normalized:
      * <ul>
      * <li>all white space characters will be condensed into at most one when
      * between words.</li>
      * <li>new line characters will be ignored and replaced with one white
      * space character</li>
      * <li>white space characters after the opening tags and before the closing
      * tags will be trimmed</li>
      *
      * @param value
      * <code>true</code> if whitespace is normalized,
      * <code>false</code> otherwise.
      */
     public void setWhitespaceNormalized(boolean value) {
         model.setWhitespaceNormalized(value);
     }

     /**
      * Tests whether whitespace inside paragraph and list item is normalized.
      *
      * @see #setWhitespaceNormalized(boolean)
      * @return <code>true</code> if whitespace is normalized,
      * <code>false</code> otherwise.
      */
     public boolean isWhitespaceNormalized() {
         return model.isWhitespaceNormalized();
     }

     /**
      * Disposes the internal menu if created and sets the menu provided as a
      * parameter.
      *
      * @param menu
      * the menu to associate with this text control
      */
     public void setMenu(Menu menu) {
         Menu currentMenu = super.getMenu();
         if (currentMenu != null && INTERNAL_MENU.equals(currentMenu.getData())) {
             // internal menu set
 if (menu != null) {
                 currentMenu.dispose();
                 super.setMenu(menu);
             }
         } else
             super.setMenu(menu);
     }

     private void createMenu() {
         Menu menu = new Menu(this);
         final MenuItem copyItem = new MenuItem(menu, SWT.PUSH);
         copyItem.setText(Messages.FormText_copy);

         SelectionListener listener = new SelectionAdapter() {
             public void widgetSelected(SelectionEvent e) {
                 if (e.widget == copyItem) {
                     copy();
                 }
             }
         };
         copyItem.addSelectionListener(listener);
         menu.addMenuListener(new MenuListener() {
             public void menuShown(MenuEvent e) {
                 copyItem.setEnabled(canCopy());
             }

             public void menuHidden(MenuEvent e) {
             }
         });
         menu.setData(INTERNAL_MENU);
         super.setMenu(menu);
     }

     /**
      * Returns the hyperlink settings that are in effect for this control.
      *
      * @return current hyperlinks settings
      */
     public HyperlinkSettings getHyperlinkSettings() {
         return model.getHyperlinkSettings();
     }

     /**
      * Sets the hyperlink settings to be used for this control. Settings will
      * affect things like hyperlink color, rendering style, cursor etc.
      *
      * @param settings
      * hyperlink settings for this control
      */
     public void setHyperlinkSettings(HyperlinkSettings settings) {
         model.setHyperlinkSettings(settings);
     }

     /**
      * Adds a listener that will handle hyperlink events.
      *
      * @param listener
      * the listener to add
      */
     public void addHyperlinkListener(IHyperlinkListener listener) {
         if (listeners == null)
             listeners = new ListenerList();
         listeners.add(listener);
     }

     /**
      * Removes the hyperlink listener.
      *
      * @param listener
      * the listener to remove
      */
     public void removeHyperlinkListener(IHyperlinkListener listener) {
         if (listeners == null)
             return;
         listeners.remove(listener);
     }

     /**
      * Adds a selection listener. A Selection event is sent by the widget when
      * the selection has changed.
      * <p>
      * <code>widgetDefaultSelected</code> is not called for FormText.
      * </p>
      *
      * @param listener
      * the listener
      * @exception SWTException
      * <ul>
      * <li>ERROR_WIDGET_DISPOSED - if the receiver has been
      * disposed</li>
      * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the
      * thread that created the receiver</li>
      * </ul>
      * @exception IllegalArgumentException
      * <ul>
      * <li>ERROR_NULL_ARGUMENT when listener is null</li>
      * </ul>
      * @since 3.1
      */
     public void addSelectionListener(SelectionListener listener) {
         checkWidget();
        if (listener == null) {
            SWT.error(SWT.ERROR_NULL_ARGUMENT);
        }
        TypedListener typedListener = new TypedListener(listener);
        addListener(SWT.Selection, typedListener);
    }

    /**
     * Removes the specified selection listener.
     * <p>
     *
     * @param listener
     * the listener
     * @exception SWTException
     * <ul>
     * <li>ERROR_WIDGET_DISPOSED - if the receiver has been
     * disposed</li>
     * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the
     * thread that created the receiver</li>
     * </ul>
     * @exception IllegalArgumentException
     * <ul>
     * <li>ERROR_NULL_ARGUMENT when listener is null</li>
     * </ul>
     * @since 3.1
     */
    public void removeSelectionListener(SelectionListener listener) {
        checkWidget();
        if (listener == null) {
            SWT.error(SWT.ERROR_NULL_ARGUMENT);
        }
        removeListener(SWT.Selection, listener);
    }

    /**
     * Returns the selected text.
     * <p>
     *
     * @return selected text, or an empty String if there is no selection.
     * @exception SWTException
     * <ul>
     * <li>ERROR_WIDGET_DISPOSED - if the receiver has been
     * disposed</li>
     * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the
     * thread that created the receiver</li>
     * </ul>
     * @since 3.1
     */

    public String getSelectionText() {
        checkWidget();
        if (selData != null)
            return selData.getSelectionText();
        return ""; //$NON-NLS-1$
 }

    /**
     * Tests if the text is selected and can be copied into the clipboard.
     *
     * @return <code>true</code> if the selected text can be copied into the
     * clipboard, <code>false</code> otherwise.
     * @since 3.1
     */
    public boolean canCopy() {
        return selData != null && selData.canCopy();
    }

    /**
     * Copies the selected text into the clipboard. Does nothing if no text is
     * selected or the text cannot be copied for any other reason.
     *
     * @since 3.1
     */

    public void copy() {
        if (!canCopy())
            return;
        Clipboard clipboard = new Clipboard(getDisplay());
        Object [] o = new Object [] { getSelectionText() };
        Transfer[] t = new Transfer[] { TextTransfer.getInstance() };
        clipboard.setContents(o, t);
        clipboard.dispose();
    }

    /**
     * Returns the reference of the hyperlink that currently has keyboard focus,
     * or <code>null</code> if there are no hyperlinks in the receiver or no
     * hyperlink has focus at the moment.
     *
     * @return href of the selected hyperlink or <code>null</code> if none
     * selected.
     * @since 3.1
     */
    public Object getSelectedLinkHref() {
        IHyperlinkSegment link = getSelectedLink();
        return link != null ? link.getHref() : null;
    }

    /**
     * Returns the text of the hyperlink that currently has keyboard focus, or
     * <code>null</code> if there are no hyperlinks in the receiver or no
     * hyperlink has focus at the moment.
     *
     * @return text of the selected hyperlink or <code>null</code> if none
     * selected.
     * @since 3.1
     */
    public String getSelectedLinkText() {
        IHyperlinkSegment link = getSelectedLink();
        return link != null ? link.getText() : null;
    }

    private IHyperlinkSegment getSelectedLink() {
        IFocusSelectable segment = model.getSelectedSegment();
        if (segment != null && segment instanceof IHyperlinkSegment)
            return (IHyperlinkSegment) segment;
        return null;
    }

    private void initAccessible() {
        Accessible accessible = getAccessible();
        accessible.addAccessibleListener(new AccessibleAdapter() {
            public void getName(AccessibleEvent e) {
                if (e.childID == ACC.CHILDID_SELF)
                    e.result = model.getAccessibleText();
                else {
                    int linkCount = model.getHyperlinkCount();
                    if (e.childID >= 0 && e.childID < linkCount) {
                        IHyperlinkSegment link = model.getHyperlink(e.childID);
                        e.result = link.getText();
                    }
                }
            }

            public void getHelp(AccessibleEvent e) {
                e.result = getToolTipText();
                int linkCount = model.getHyperlinkCount();
                if (e.result == null && e.childID >= 0 && e.childID < linkCount) {
                    IHyperlinkSegment link = model.getHyperlink(e.childID);
                    e.result = link.getText();
                }
            }
        });
        accessible.addAccessibleControlListener(new AccessibleControlAdapter() {
            public void getChildAtPoint(AccessibleControlEvent e) {
                Point pt = toControl(new Point(e.x, e.y));
                IHyperlinkSegment link = model.findHyperlinkAt(pt.x, pt.y);
                if (link != null)
                    e.childID = model.indexOf(link);
                else
                    e.childID = ACC.CHILDID_SELF;
            }

            public void getLocation(AccessibleControlEvent e) {
                Rectangle location = null;
                if (e.childID != ACC.CHILDID_SELF
                        && e.childID != ACC.CHILDID_NONE) {
                    int index = e.childID;
                    IHyperlinkSegment link = model.getHyperlink(index);
                    if (link != null) {
                        location = link.getBounds();
                    }
                }
                if (location == null) {
                    location = getBounds();
                }
                Point pt = toDisplay(new Point(location.x, location.y));
                e.x = pt.x;
                e.y = pt.y;
                e.width = location.width;
                e.height = location.height;
            }

            public void getFocus(AccessibleControlEvent e) {
                int childID = ACC.CHILDID_NONE;

                if (isFocusControl()) {
                    int selectedIndex = model.getSelectedSegmentIndex();
                    if (selectedIndex == -1) {
                        childID = ACC.CHILDID_SELF;
                    } else {
                        childID = selectedIndex;
                    }
                }
                e.childID = childID;
            }
            
            public void getDefaultAction (AccessibleControlEvent e) {
                if (model.getHyperlinkCount() > 0) {
                    e.result = SWT.getMessage ("SWT_Press"); //$NON-NLS-1$
 }
            }

            public void getChildCount(AccessibleControlEvent e) {
                e.detail = model.getHyperlinkCount();
            }

            public void getRole(AccessibleControlEvent e) {
                int role = 0;
                int childID = e.childID;
                int linkCount = model.getHyperlinkCount();
                if (childID == ACC.CHILDID_SELF) {
                    if (linkCount > 0) {
                        role = ACC.ROLE_LINK;
                    } else {
                        role = ACC.ROLE_TEXT;
                    }
                } else if (childID >= 0 && childID < linkCount) {
                    role = ACC.ROLE_LINK;
                }
                e.detail = role;
            }

            public void getSelection(AccessibleControlEvent e) {
                int selectedIndex = model.getSelectedSegmentIndex();
                e.childID = (selectedIndex == -1) ? ACC.CHILDID_NONE
                        : selectedIndex;
            }

            public void getState(AccessibleControlEvent e) {
                int linkCount = model.getHyperlinkCount();
                int selectedIndex = model.getSelectedSegmentIndex();
                int state = 0;
                int childID = e.childID;
                if (childID == ACC.CHILDID_SELF) {
                    state = ACC.STATE_NORMAL;
                } else if (childID >= 0 && childID < linkCount) {
                    state = ACC.STATE_SELECTABLE;
                    if (isFocusControl()) {
                        state |= ACC.STATE_FOCUSABLE;
                    }
                    if (selectedIndex == childID) {
                        state |= ACC.STATE_SELECTED;
                        if (isFocusControl()) {
                            state |= ACC.STATE_FOCUSED;
                        }
                    }
                }
                state |= ACC.STATE_READONLY;
                e.detail = state;
            }

            public void getChildren(AccessibleControlEvent e) {
                int linkCount = model.getHyperlinkCount();
                Object [] children = new Object [linkCount];
                for (int i = 0; i < linkCount; i++) {
                    children[i] = new Integer (i);
                }
                e.children = children;
            }

            public void getValue(AccessibleControlEvent e) {
                // e.result = model.getAccessibleText();
 }
        });
    }

    private void startSelection(MouseEvent e) {
        inSelection = true;
        selData = new SelectionData(e);
        redraw();
        Form form = FormUtil.getForm(this);
        if (form != null)
            form.setSelectionText(this);
    }

    private void endSelection(MouseEvent e) {
        inSelection = false;
        if (selData != null) {
            if (!selData.isEnclosed())
                selData = null;
            else
                computeSelection();
        }
        notifySelectionChanged();
    }

    private void computeSelection() {
        GC gc = new GC(this);
        Paragraph[] paragraphs = model.getParagraphs();
        IHyperlinkSegment selectedLink = getSelectedLink();
        if (getDisplay().getFocusControl() != this)
            selectedLink = null;
        for (int i = 0; i < paragraphs.length; i++) {
            Paragraph p = paragraphs[i];
            if (i > 0)
                selData.markNewLine();
            p.computeSelection(gc, resourceTable, selectedLink, selData);
        }
        gc.dispose();
    }

    void clearSelection() {
        selData = null;
        if (!isDisposed()) {
            redraw();
            notifySelectionChanged();
        }
    }

    private void notifySelectionChanged() {
        Event event = new Event();
        event.widget = this;
        event.display = this.getDisplay();
        event.type = SWT.Selection;
        notifyListeners(SWT.Selection, event);
        getAccessible().selectionChanged();
    }

    private void handleDrag(MouseEvent e) {
        if (selData != null) {
            ScrolledComposite scomp = FormUtil.getScrolledComposite(this);
            if (scomp != null) {
                FormUtil.ensureVisible(scomp, this, e);
            }
            selData.update(e);
            redraw();
        }
    }

    private void handleMouseClick(MouseEvent e, boolean down) {
        if (DEBUG_FOCUS)
            System.out.println("FormText: mouse click(" + down + ")"); //$NON-NLS-1$ //$NON-NLS-2$
 if (down) {
            // select a hyperlink
 mouseFocus = true;
            IHyperlinkSegment segmentUnder = model.findHyperlinkAt(e.x, e.y);
            if (segmentUnder != null) {
                IHyperlinkSegment oldLink = getSelectedLink();
                if (getDisplay().getFocusControl() != this) {
                    setFocus();
                }
                model.selectLink(segmentUnder);
                enterLink(segmentUnder, e.stateMask);
                paintFocusTransfer(oldLink, segmentUnder);
            }
            if (e.button == 1) {
                startSelection(e);
                armed = segmentUnder;
            }
            else {
            }
        } else {
            if (e.button == 1) {
                endSelection(e);
                IHyperlinkSegment segmentUnder = model
                        .findHyperlinkAt(e.x, e.y);
                if (segmentUnder != null && armed == segmentUnder && selData == null) {
                    activateLink(segmentUnder, e.stateMask);
                    armed = null;
                }
            }
            mouseFocus = false;
        }
    }

    private void handleMouseHover(MouseEvent e) {
    }

    private void updateTooltipText(ParagraphSegment segment) {
        String tooltipText = null;
        if (segment != null) {
            tooltipText = segment.getTooltipText();
        }
        String currentTooltipText = getToolTipText();

        if ((currentTooltipText != null && tooltipText == null)
                || (currentTooltipText == null && tooltipText != null))
            setToolTipText(tooltipText);
    }

    private void handleMouseMove(MouseEvent e) {
        if (inSelection) {
            handleDrag(e);
            return;
        }
        ParagraphSegment segmentUnder = model.findSegmentAt(e.x, e.y);
        updateTooltipText(segmentUnder);
        if (segmentUnder == null) {
            if (entered != null) {
                exitLink(entered, e.stateMask);
                paintLinkHover(entered, false);
                entered = null;
            }
            setCursor(null);
        } else {
            if (segmentUnder instanceof IHyperlinkSegment) {
                IHyperlinkSegment linkUnder = (IHyperlinkSegment) segmentUnder;
                if (entered!=null && linkUnder!=entered) {
                    // Special case: links are so close that there are 0 pixels between.
 // Must exit the link before entering the next one.
 exitLink(entered, e.stateMask);
                    paintLinkHover(entered, false);
                    entered = null;
                }
                if (entered == null) {
                    entered = linkUnder;
                    enterLink(linkUnder, e.stateMask);
                    paintLinkHover(entered, true);
                    setCursor(model.getHyperlinkSettings().getHyperlinkCursor());
                }
            } else {
                if (entered != null) {
                    exitLink(entered, e.stateMask);
                    paintLinkHover(entered, false);
                    entered = null;
                }
                if (segmentUnder instanceof TextSegment)
                    setCursor(model.getHyperlinkSettings().getTextCursor());
                else
                    setCursor(null);
            }
        }
    }

    private boolean advance(boolean next) {
        if (DEBUG_FOCUS)
            System.out.println("Advance: next=" + next); //$NON-NLS-1$
 IFocusSelectable current = model.getSelectedSegment();
        if (current != null && current instanceof IHyperlinkSegment)
            exitLink((IHyperlinkSegment) current, SWT.NULL);
        IFocusSelectable newSegment = null;
        boolean valid = false;
        // get the next segment that can accept focus. Links
 // can always accept focus but controls may not
 while (!valid) {
            if (!model.traverseFocusSelectableObjects(next))
                break;
            newSegment = model.getSelectedSegment();
            if (newSegment == null)
                break;
            valid = setControlFocus(next, newSegment);
        }
        IHyperlinkSegment newLink = newSegment instanceof IHyperlinkSegment ? (IHyperlinkSegment) newSegment
                : null;
        if (valid)
            enterLink(newLink, SWT.NULL);
        IHyperlinkSegment oldLink = current instanceof IHyperlinkSegment ? (IHyperlinkSegment) current
                : null;
        if (oldLink != null || newLink != null)
            paintFocusTransfer(oldLink, newLink);
        if (newLink != null)
            ensureVisible(newLink);
        if (newLink != null)
            getAccessible().setFocus(model.getSelectedSegmentIndex());
        return !valid;
    }

    private boolean setControlFocus(boolean next, IFocusSelectable selectable) {
        controlFocusTransfer = true;
        boolean result = selectable.setFocus(resourceTable, next);
        controlFocusTransfer = false;
        return result;
    }

    private void handleFocusChange() {
        if (DEBUG_FOCUS) {
            System.out.println("Handle focus change: hasFocus=" + hasFocus //$NON-NLS-1$
 + ", mouseFocus=" + mouseFocus); //$NON-NLS-1$
 }
        if (hasFocus) {
            boolean advance = true;
            if (!mouseFocus) {
                // if (model.restoreSavedLink() == false)
 boolean valid = false;
                IFocusSelectable selectable = null;
                while (!valid) {
                    if (!model.traverseFocusSelectableObjects(advance))
                        break;
                    selectable = model.getSelectedSegment();
                    if (selectable == null)
                        break;
                    valid = setControlFocus(advance, selectable);
                }
                if (selectable != null)
                    ensureVisible(selectable);
                if (selectable instanceof IHyperlinkSegment) {
                    enterLink((IHyperlinkSegment) selectable, SWT.NULL);
                    paintFocusTransfer(null, (IHyperlinkSegment) selectable);
                }
            }
        } else {
            paintFocusTransfer(getSelectedLink(), null);
            model.selectLink(null);
        }
    }

    private void enterLink(IHyperlinkSegment link, int stateMask) {
        if (link == null || listeners == null)
            return;
        int size = listeners.size();
        HyperlinkEvent he = new HyperlinkEvent(this, link.getHref(), link
                .getText(), stateMask);
        Object [] listenerList = listeners.getListeners();
        for (int i = 0; i < size; i++) {
            IHyperlinkListener listener = (IHyperlinkListener) listenerList[i];
            listener.linkEntered(he);
        }
    }

    private void exitLink(IHyperlinkSegment link, int stateMask) {
        if (link == null || listeners == null)
            return;
        int size = listeners.size();
        HyperlinkEvent he = new HyperlinkEvent(this, link.getHref(), link
                .getText(), stateMask);
        Object [] listenerList = listeners.getListeners();
        for (int i = 0; i < size; i++) {
            IHyperlinkListener listener = (IHyperlinkListener) listenerList[i];
            listener.linkExited(he);
        }
    }

    private void paintLinkHover(IHyperlinkSegment link, boolean hover) {
        GC gc = new GC(this);
        HyperlinkSettings settings = getHyperlinkSettings();
        Color newFg = hover ? settings.getActiveForeground() : settings
                .getForeground();
        if (newFg != null)
            gc.setForeground(newFg);
        gc.setBackground(getBackground());
        gc.setFont(getFont());
        boolean selected = (link == getSelectedLink());
        ((ParagraphSegment) link).paint(gc, hover, resourceTable, selected,
                selData, null);
        gc.dispose();
    }

    private void activateSelectedLink() {
        IHyperlinkSegment link = getSelectedLink();
        if (link != null)
            activateLink(link, SWT.NULL);
    }

    private void activateLink(IHyperlinkSegment link, int stateMask) {
        setCursor(model.getHyperlinkSettings().getBusyCursor());
        if (listeners != null) {
            int size = listeners.size();
            HyperlinkEvent e = new HyperlinkEvent(this, link.getHref(), link
                    .getText(), stateMask);
            Object [] listenerList = listeners.getListeners();
            for (int i = 0; i < size; i++) {
                IHyperlinkListener listener = (IHyperlinkListener) listenerList[i];
                listener.linkActivated(e);
            }
        }
        if (!isDisposed() && model.linkExists(link)) {
            setCursor(model.getHyperlinkSettings().getHyperlinkCursor());
        }
    }

    private void ensureBoldFontPresent(Font regularFont) {
        Font boldFont = (Font) resourceTable.get(FormTextModel.BOLD_FONT_ID);
        if (boldFont != null)
            return;
        boldFont = FormUtil.createBoldFont(getDisplay(), regularFont);
        resourceTable.put(FormTextModel.BOLD_FONT_ID, boldFont);
    }

    private void paint(PaintEvent e) {
        GC gc = e.gc;
        gc.setFont(getFont());
        ensureBoldFontPresent(getFont());
        gc.setForeground(getForeground());
        gc.setBackground(getBackground());
        repaint(gc, e.x, e.y, e.width, e.height);
    }

    private void repaint(GC gc, int x, int y, int width, int height) {
        Image textBuffer = new Image(getDisplay(), width, height);
        Color bg = getBackground();
        Color fg = getForeground();
        if (!getEnabled()) {
            bg = getDisplay().getSystemColor(SWT.COLOR_WIDGET_BACKGROUND);
            fg = getDisplay().getSystemColor(SWT.COLOR_WIDGET_NORMAL_SHADOW);
        }
        GC textGC = new GC(textBuffer, gc.getStyle());
        textGC.setForeground(fg);
        textGC.setBackground(bg);
        textGC.setFont(getFont());
        textGC.fillRectangle(0, 0, width, height);
        Rectangle repaintRegion = new Rectangle(x, y, width, height);

        Paragraph[] paragraphs = model.getParagraphs();
        IHyperlinkSegment selectedLink = getSelectedLink();
        if (getDisplay().getFocusControl() != this)
            selectedLink = null;
        for (int i = 0; i < paragraphs.length; i++) {
            Paragraph p = paragraphs[i];
            p
                    .paint(textGC, repaintRegion, resourceTable, selectedLink,
                            selData);
        }
        textGC.dispose();
        gc.drawImage(textBuffer, x, y);
        textBuffer.dispose();
    }

    private int getParagraphSpacing(int lineHeight) {
        return lineHeight / 2;
    }

    private void paintFocusTransfer(IHyperlinkSegment oldLink,
            IHyperlinkSegment newLink) {
        GC gc = new GC(this);
        Color bg = getBackground();
        Color fg = getForeground();
        gc.setFont(getFont());
        if (oldLink != null) {
            gc.setBackground(bg);
            gc.setForeground(fg);
            oldLink.paintFocus(gc, bg, fg, false, null);
        }
        if (newLink != null) {
            // ensureVisible(newLink);
 gc.setBackground(bg);
            gc.setForeground(fg);
            newLink.paintFocus(gc, bg, fg, true, null);
        }
        gc.dispose();
    }

    private void ensureVisible(IFocusSelectable segment) {
        if (mouseFocus) {
            mouseFocus = false;
            return;
        }
        if (segment == null)
            return;
        Rectangle bounds = segment.getBounds();
        ScrolledComposite scomp = FormUtil.getScrolledComposite(this);
        if (scomp == null)
            return;
        Point origin = FormUtil.getControlLocation(scomp, this);
        origin.x += bounds.x;
        origin.y += bounds.y;
        FormUtil.ensureVisible(scomp, origin, new Point(bounds.width,
                bounds.height));
    }

    /**
     * Overrides the method by fully trusting the layout manager (computed width
     * or height may be larger than the provider width or height hints). Callers
     * should be prepared that the computed width is larger than the provided
     * wHint.
     *
     * @see org.eclipse.swt.widgets.Composite#computeSize(int, int, boolean)
     */
    public Point computeSize(int wHint, int hHint, boolean changed) {
        checkWidget();
        Point size;
        FormTextLayout layout = (FormTextLayout) getLayout();
        if (wHint == SWT.DEFAULT || hHint == SWT.DEFAULT) {
            size = layout.computeSize(this, wHint, hHint, changed);
        } else {
            size = new Point(wHint, hHint);
        }
        Rectangle trim = computeTrim(0, 0, size.x, size.y);
        if (DEBUG_TEXTSIZE)
            System.out.println("FormText Computed size: "+trim); //$NON-NLS-1$
 return new Point(trim.width, trim.height);
    }

    private void disposeResourceTable(boolean disposeBoldFont) {
        if (disposeBoldFont) {
            Font boldFont = (Font) resourceTable
                    .get(FormTextModel.BOLD_FONT_ID);
            if (boldFont != null) {
                boldFont.dispose();
                resourceTable.remove(FormTextModel.BOLD_FONT_ID);
            }
        }
        ArrayList imagesToRemove = new ArrayList ();
        for (Enumeration enm = resourceTable.keys(); enm.hasMoreElements();) {
            String key = (String ) enm.nextElement();
            if (key.startsWith(ImageSegment.SEL_IMAGE_PREFIX)) {
                Object obj = resourceTable.get(key);
                if (obj instanceof Image) {
                    Image image = (Image) obj;
                    if (!image.isDisposed()) {
                        image.dispose();
                        imagesToRemove.add(key);
                    }
                }
            }
        }
        for (int i = 0; i < imagesToRemove.size(); i++) {
            resourceTable.remove(imagesToRemove.get(i));
        }
    }

    /*
     * (non-Javadoc)
     *
     * @see org.eclipse.swt.widgets.Control#setEnabled(boolean)
     */
    public void setEnabled(boolean enabled) {
        super.setEnabled(enabled);
        redraw();
    }

    /* (non-Javadoc)
     * @see org.eclipse.swt.widgets.Control#setFocus()
     */
    public boolean setFocus() {
        mouseFocus = true;
        FormUtil.setFocusScrollingEnabled(this, false);
        boolean result = super.setFocus();
        mouseFocus = false;
        FormUtil.setFocusScrollingEnabled(this, true);
        return result;
    }
}

